Aerosol insecticides, generally, consist of an oily concentrate consisting of an effective ingredient (such as an insecticide) and a propellant. Flammable liquefied petroleum gas (LPG) is used for a propellant, thereby causing to high flammability and high ignitability. Therefore, for the purpose of improving safety against fire, such as flammability and ignitability, aerosol insecticides, containing a kerosene solution, dimethyl ether and LPG in a specific proportion, has been applied for a patent (or example, Japanese Unexamined Patent Publication Nos. 1976-67732, 1976-70826, etc.). This satisfies the conditions for the weak flammability (flame length: 45 cm or shorter, lower limit explosion concentration: 0.13 g/L (liter) or higher) in the flammability classification defined by the former Ministry of International Trade and Industry notice No. 557 (Oct. 15, 1965), in a flame length test and an explosion concentration test. When the above-mentioned aerosol insecticide is sprayed, the propellant is vaporized faster than the concentrate as the concentrate is dispersed in a space. Therefore, if the concentrate itself has a flash point, its safety against fire cannot be high. In recent years, in consideration of safety such as ignitability and toxicity against a living body, development of water-based aerosol insecticides is going ahead one after another.
Though such water-based aerosol insecticide become high in safety against fire through using a water-based concentrate, corrosive property is caused to a tinplate-made aerosol container, commonly used for aerosol insecticides, due to the contained water. In addition, an aqueous insecticide ingredient should be selected, but such insecticide ingredient cannot attach effectively to a surface of an oleophilic pest, causing a problem in efficacy. Moreover, drying characteristics becomes worse, resulting in insufficient usability.
As means for solving these problems, a W/O type emulsion aerosol insecticide consisting of an effective ingredient, an oleophilic solvent such as kerosene, an emulsifier, LPG and the like was proposed (for example, Japanese Examined Patent Publication No. 1980-2401, Japanese Patent No. 2855736, etc.). In this insecticide, a water phase is dispersed in an oil phase kerosene and LPG), and thereby water merely contacts directly to the inner surface of the container to prevent corrosion. However, such aerosol product of a W/O type emulsion has problems in stability of emulsion as well as problems of complicated manufacturing processes.
A technological subject of the present invention is to provide a one-component type aerosol composition high in safety against fire, capable of preventing corrosion of the container, and also capable of attaching effectively the effective ingredient to an oleophilic surface.